This invention relates to a device for rock drilling comprising a drill boom, a boom bracket for supporting the drill boom, a rock drilling machine carried swingably with respect to the drill boom and the boom bracket and equipped with a drill steel, a pressure fluid actuated adjusting motor means connected to the drill boom for positioning the rock drilling machine relative to the drill boom, and a servo system which controls the adjusting motor means during drilling in such a way that the rock drilling machine is fed along a desired drilling axis as a consequence of a feed movement applied by the drill boom.
In previously disclosed devices of this type (Swedish Pat. No. 343,104), corresponding to U.S. Pat. No. 3,724,559 the use of the servo system has caused function trouble due to the complexity of its construction.
The object of the present invention is to considerably simplify the control method and the construction of the control system in order to achieve a more reliable function in extremely light self-drilling drilling equipment. This object is attained by the characterizing features in the claims following hereinafter.